Trump Doesn’t Know What He Wants to Do in Syria. He Needs to Figure It Out—Fast.

In March 2003, during the invasion of Iraq, then–Maj. Gen. David Petraeus turned to embedded reporter Linda Robinson and famously asked: “Tell me how this ends.”

That question has never fully been answered in Iraq, despite the expenditure of huge sums of American blood and treasure. And yet, it’s the right question to ask of any military endeavor, because it links current operations to a desired future objective, lest all that blood and treasure be wasted for war’s own sake.

The same question ought to be asked now, the day after President Donald Trump ordered cruise missiles to strike a Syrian airfield in response to the brutal killing of Syrian civilians with chemical weapons two days earlier. What comes next, and how this ultimately ends, depends on what military steps come next—by the United States, as well as the Russians, Syrians, Iranians, and others active in the region. Moreover, Thursday’s strike complicates nearly everything we are now doing in Syria, potentially setting in motion a chain reaction of conflict whose end is difficult to foresee or control.

Thursday night’s strike hit what it aimed at: a Syrian airfield that reportedly hosted the aircraft responsible for the attack, as well as the logistics units responsible for supporting Syrian ground forces in the region. More than 50 cruise missiles hit the site, making this more than a “pinprick” attack but substantially less than what the U.S. could have done with our Navy and Air Force. Based on comments by the president and his senior advisers, the bombing represents a more forceful way of telling the Syrians to abstain from chemical warfare. Whether the bombings will produce the intended result—or whether the U.S. will need to conduct more such strikes, or other military operations to inflict pain on the Syrian regime—remains to be seen.

However, President Trump also alluded to other objectives in Syria beyond merely disciplining Bashar al-Assad and his military for their use of chemical weapons—what he termed a “vital national security interest.” The president talked of the “refugee crisis” in Syria that “continues to destabilize, threatening the United States and its allies.” And he spoke about the broader civil war and its impact on civilians, ending his statement on a broadly aspirational note that the U.S. would stand for justice in the world. In the days leading up to the missile strike, Trump’s advisers also alluded to a range of other goals, including the easing out (or forceful replacement) of Assad, with presumably some U.S. role in rebuilding post-Assad, postwar Syria. It’s worth pausing on each of these statements, because they signal potential next steps in Syria, and potential sequels as well.

If Trump is serious about doing something about the Syria refugee crisis, that foreshadows a certain set of military options. The most obvious of these is the combination of a “no-fly zone” and the establishment of some safe zone on the ground for Syrian civilians. The U.S. military has set up no-fly zones before in Iraq and other parts of the world. This would likely involve some further bombing to degrade Syrian air defenses and command networks, followed by the establishment of a persistent air presence over Syria capable of shooting down Syrian aircraft. These operations require manned aircraft to execute, putting U.S. pilots and aircrews at significant risk, especially during the initial phases of attacking Syrian’s vaunted air defenses. Moreover, as my colleagues Ilan Goldenberg and Nick Heras note, Russian forces are currently deployed at Syrian bases throughout the countryside. Any significant attacks on Syria will necessarily mean U.S. attacks that kill Russian troops, escalating the conflict significantly.

While no one in the Trump administration has called explicitly for a safe zone on the ground, it’s difficult to see how a no-fly zone alone would protect Syria’s civilians without some ground sanctuary where they can reside and receive humanitarian assistance. Syria has a large army that can (and likely will) continue its slaughter even without air support. Setting up such a safe zone would require the introduction of U.S. ground forces in sufficient numbers—at least several thousand at first—to seize and hold territory. Setting up a safe zone would mark a major expansion of the U.S. commitment to the Syrian war, far above and beyond what exists on the ground in Iraq or Syria today.

To state an obvious point: Establishing a no-fly zone and refugee sanctuary will both be substantially more difficult now that the U.S. has made an enemy of the Assad regime. This increased enmity means more force will be needed to protect the civilians, because of the increased likelihood that Syria will contest the U.S. moves.

Relatedly, there is the ongoing effort by both the U.S. and Syria to combat ISIS. Early reports suggest that, in addition to damaging elements of the Syrian air force, the Thursday airstrike hit some of the Syrian army units fighting ISIS. As a consequence, Syria’s counter-ISIS efforts may be degraded, forcing Syrian army units to devote more attention to protecting themselves. That, in the end, could hurt U.S. interests in the region and force us and our proxies to take on more of the ISIS fight ourselves.

Thursday’s strike also upsets the uneasy détente that had grown between the U.S., Russia, and other countries operating inside Syria. This relationship had never matured to the point where U.S. and Russian forces were fighting together like they did during World War II, but at least there was the potential for further cooperation down the line. Not anymore.

Further, as noted above, the Russians’ expansive presence in Syria increases the stakes of American involvement. Indeed, Russia may decide to help its client state Syria more as the result of this airstrike, frustrating further U.S. action, particularly if such action comes to include regime change.

Before this week, the Trump administration never clearly articulated its position on whether Assad should stay or go. Assad’s barbaric murder of civilians with chemical weapons appeared to change that, although Secretary of State Rex Tillerson and National Security Adviser H.R. McMaster stopped well short of saying they wanted immediate regime change by force. Whether the U.S. wants regime change—and how—remains the great unanswered question after Thursday’s missile strike.

Regime change in Syria will not happen on its own. Assad must be forced out, either through a coalition of U.S., Arab, and indigenous forces that puts pressure on the regime or via more direct action by the U.S. and its allies. The post-Assad situation looks grim, because of the brutality of Syria’s civil war, its enormous population dislocations, and the power vacuum that will follow Assad. Some type of post-Assad reconstruction effort must come together to put Syria back together if (or when) Assad goes. Arguably, only the U.S. has the experience and capability to lead such an effort. But in the wake of Iraq and Afghanistan, and the Trump administration’s political commitments to put America first, it’s unclear the nation or its leaders have the stomach for what may be required.

Few people in government know more about the consequences of regime change in the Middle East than McMaster, Defense Secretary James Mattis, and Chairman of the Joint Chiefs Gen. Joseph Dunford. All three men have spent the majority of their adult lives fighting in Iraq or adjacent countries, or preparing to fight there. They understand well the costs and consequences of combat, and the great uncertainty that exists when nations go to war. So far, the president’s statement Thursday night, coupled with a lack of military and diplomatic follow-up to the strikes, suggests the U.S. has not yet decided what to do next, much less developed a broader strategy for Syria. That needs to change. This week’s strikes marked an inflection point for U.S. involvement in the Syrian conflict; we are now part of this war. If the U.S. wants to achieve the objectives described by President Trump, it must do more than lob a few cruise missiles into the desert.